Treatments, such as a culture medium filtering treatment that is a filtering treatment performed for supplying a culture solution into a cell culture tank and a virus removing treatment performed in a manufacturing process of pharmaceutical preparations, are performed by connecting a hollow fiber membrane module to a liquid treatment circuit.
Since such culture medium filtering treatment and virus removing treatment are required to be performed under a strict aseptic condition, the hollow fiber membrane module is subjected, before shipping, to a steam sterilization treatment in a state in which the hollow fiber membrane module is filled with a liquid and closed by directly attaching a cap into its liquid port. After the steam sterilization treatment, the hollow fiber membrane is shipped out with its aseptic condition maintained.
A (dry-state) membrane module whose membrane is dry requires a filter, which has been wet for a pinhole test, to be dried, and spends much time and heat (energy). On the other hand, a membrane module filled with a liquid can be used even after long-term storage and does not require the filling liquid to be removed from inside the membrane module after the pinhole test conducted before the shipping, and it is therefore preferable in terms of its reduced number of manufacturing steps.